The present invention relates to back supports and more particularly to back supports used in seatbacks.
A variety of seatback back support devices provide added support and comfort to a person's back. These devices are especially common in vehicle seats or office chairs as lumbar supports.
Typically, back supports include several drawbacks and limitations. First, most commonly used mechanical back supports are composed of a relatively large number of parts. Typically, a number of horizontal supporting members are riveted to a pair of vertical supports. Further, a central tension bar is connected to the horizontal members. Such supports are subtended longitudinally to form an arch of varying degree by adjusting the tension bar. A complicated gearing mechanism is needed to adjust the tension bar. A significant drawback is presented by the difficulty associated with assembling such back support systems.
Second, typical back supports are relatively heavy and add undesirable weight to automotive vehicles, thereby limiting the availability of such supports.
Third, such supports are rigid and, therefore, typically require a complex spring mounting system within the seatback to provide comfort to a person using the support. Such spring mounting systems are relatively complicated and expensive to manufacture. Such spring mounting systems also increase the weight of the seat.
Fourth, typical back supports form a single apex within the supporting arch. The apex preferably should be at varying locations within the seatback to provide support to a variety of people. Therefore, complicated mounting and gearing mechanisms are needed to adjust the position of the support apex relative to the seat. Such mounting and gearing mechanisms are subject to breakdown and further add undesirable weight to the seat.
All the above-described limitations and drawbacks are undesirable. Therefore, an object of the present invention is to provide a flexible, strong back support that simplifies manufacture and assembly of back supports and, correspondingly, vehicle seats or chairs. Another object of the present invention is to provide a back support that has an automatically adjusting apex that effectively moves along the longitudinal length of the back support. A back support in accordance with the present invention therefore properly conforms to a user's back to provide greater comfort and support.